A Clinical Evaluation of Marula-Derived Ceramide Cream on Skin Barrier Function Enhancement

Efficacy of Marula Oil-Derived Ceramide Cream in Improving Skin Barrier Function: A Clinical Evaluation

Previously, the investigators have demonstrated in vitro the excellent efficacy of marula oil-derived ceramide NPs in enhancing skin barrier function. The investigators's findings show that marula oil-derived ceramide NPs not only significantly reduces levels of inflammatory cytokines but also promotes the expression of key proteins in skin barrier integrity. These results suggest that marula oil-derived ceramide NPs may offer a more effective therapeutic option for skin barrier-disrupted diseases. Therefore, the investigators aim to further investigate the repair function of marula oil-derived ceramide NPs on the human epidermal barrier through a clinical trial.

Marula oil, a botanical ingredient widely utilized in the cosmetics industry, has attracted significant attention due to its exceptional skin-beneficial attributes. Characterized by its richness in monounsaturated fatty acids, predominantly oleic acid, and antioxidants, marula oil exhibits potent moisturizing, anti-inflammatory, anti-aging, and antioxidant activities. Notably, despite sharing a similar fatty acid profile with olive oil, marula oil demonstrates tenfold greater resistance to lipid oxidation. Additionally, the fatty acid chain lengths of marula oil, spanning from C14 to C22, closely align with those of human skin ceramides, positioning it as an ideal precursor for the synthesis of plant-derived ceramide NPs.

Previously, the investigators has demonstrated in vitro that marula oil-derived ceramide NPs have excellent efficacy in enhancing skin barrier function. The investigators' findings show that marula oil-derived ceramide NPs not only significantly reduce levels of inflammatory cytokines but also promote the expression of key proteins in skin barrier integrity. These results suggest that marula oil-derived ceramide NPs may offer a more effective therapeutic option for skin barrier-disrupted diseases. Therefore, the investigators aim to further investigate the repair function of marula oil-derived ceramide NPs on the human epidermal barrier through a clinical trial.

Against this backdrop, the investigators aims to assess the efficacy of a marula oil-derived ceramide NPs cream in moisturizing, soothing, and repairing the skin barrier. A 28-day prospective study will be conducted on adult subjects, who will use the product as directed under standardized conditions. The investigation will also evaluate the suitability of the cream for sensitive skin, focusing on its non-irritating properties.

Inclusion Criteria

• Healthy females aged 18 to 60 years
• Skin types: oily, combination oily, neutral, dry, or combination dry
• Ethnicity: Asian (Chinese)
• Sensitive skin confirmed by lactic acid stinging test screening
• Transepidermal water loss (TEWL) > 15 g/h/m² in one cheek area
• Stratum corneum moisture content <50 C.U. in one cheek area
• Visual redness score 3-6 per SGS standard atlas (0-9 scale, 0.5-point increment)
• Willingness to sign photo consent form
• No significant skin lesions, scars, or excessive facial/neck hair
• Ability to comply with protocol requirements and maintain consistent lifestyle

Exclusion Criteria Refusal to sign informed consent

• Unwillingness to comply with protocol requirements
• Concurrent participation in other clinical studies
• Cosmetic/drug use on assessment day
• Pregnancy or lactation (self-reported)
• Pharmacological treatment during study
• Infectious skin diseases or atopic dermatitis
• Skin abnormalities in assessment area (e.g., moles, telangiectasia)
• Skin peeling/cosmetic procedures within 3 months prior to enrollment
• Immunosuppressant therapy within 3 months prior to enrollment
• Systemic steroid treatment or phototherapy within 1 month prior to enrollment
• Use of topical medications/special efficacy cosmetics on target area within 2 weeks prior to enrollment
• Assessment area lesions interfering with measurements
• History of severe reactions to cosmetics, drugs, or light exposure
• Principal Investigator discretion of unsuitability